Help: Silverado drivers

[mjones12]

I have a question about something that happened with my 2010 Silverado 1500 extended cab LT 5.3 V8 with towing package.

I have been towing a lighter trailer, 2,685 dry weight, and went up to a Surveyor 220, about 4,000 dry weight. Both times I have towed the new trailer, the transmission temp screen came up. It never came up on its own with the lighter trailer. I would have to scroll to that screen to view it.

There are no bells, whistles or warnings, the normal viewing screen just comes up on its own. I was towing on a slightly rolling highway today when it came up, and it showed a little over 150 degrees and topped out at 160 degrees. After I dropped the trailer and drove for a while it gradually went down to the 129-130 range. I figure I'm towing this trailer at about 5,000 pounds, well under the towing capacity and with no cargo in the truck.

To me, 160 degrees didn't seem alarmingly high, but I'm no transmission expert. I just wonder why that screen would come up when it had never done so with the other camper. By the way, I have always towed in the two/haul mode. Any ideas? Thanks

[TexasBob]

I'm pulling about 5800 lbs. and in the summer the transmission temp runs about 178F. It does not display it unless I scroll to it just to see what it is. Maximum temp? I'm not sure but I believe it is somewhere between 195 and 210.

[TexasBob]

From GM

“General Motors’ in-house towing team expert provided RV Clinic with this statement: The maximum allowable automatic transmission fluid temperature is dictated by the transmission oil itself. The oil begins to degrade significantly above 270 degrees Fahrenheit, so we design vehicles so that in all but the most extreme conditions, the fluid temperature in the transmission sump stays below 270 degrees F.

We allow for up to 285 degrees F in extreme conditions (i.e. towing a trailer with combination loaded at GCWR in Death Valley). But for customer usage anywhere else in the country, even at GCWR, transmission sump temperature should stay well below 270 degrees F. Above this point, certain internal components, such as seals, begin to disintegrate rather quickly. Although newer synthetic fluids can withstand higher temperatures we still recommend this (270F) as a maximum temperature. "

[LKicklight]

I would assume you had your tow/haul engaged..correct..if so, those temps are fine...on a fairly flat highway, I never use the tow/haul and the temps with out 2500HD usually stay around 160-180....and there are no bells are whistle that I know of...
kickster

Originally Posted by TexasBob

I'm pulling about 5800 lbs. and in the summer the transmission temp runs about 178F. It does not display it unless I scroll to it just to see what it is. Maximum temp? I'm not sure but I believe it is somewhere between 195 and 210.

[TexasBob]

When I tow I always use the tow/haul mode.

[mjones12]

Originally Posted by TexasBob

When I tow I always use the tow/haul mode.

Me, too.

[SJones42]

Them temps are fine,As for why thescreen flashes up,u got me there,I have the same year and engine and i have to scroll to my trans temp screen

[rattleNsmoke]

I would consider a ScanGauge II (approx $160 @ AutoZone) and get real engine and transmission readings plus a host of other things right from your PCM. It plugs into your data port for the OBDII and has an on-dash display box. This way you can monitor all sorts of fun stuff in real-time, all at one time. Check out this link:
ScanGauge - Trip Computer + Digitial Gauges + ScanTools

[SSmbs]

This past winter I towed 6600# for 6,000 miles with a 5.3 . I have found the transmission runs cooler and mileage does not decrease by leaving the transmission in 3rd. I had a 4 speed transmission in a 2007 new style half ton.

[mduff]

with towing package

Our TT is approximately the same weight range, no issue with towing although only a couple of times late last season. Assuming that your towing package included the transmission cooler (just a thought); we installed one on our previous 4.8 Silverado and it made a significant difference on the transmission temperature.

When I tow I always use the tow/haul mode.

It is understood that this changes the shift points for the transmission; shifts earlier, runs engine RPMs higher.

[prof_fate]

I've not gone far enough with the big TT yet but have pulled a car on a carrier 100 miles and got to 'play' a bit. 80F day, 55mph tow haul then 65 tow haul, then 60 in regular mode.
In regular mode MPG went to hell. from 15 to 13 almost immediately. I noticed nothing else. (return trip w/ empty trailer in tow haul 65mph got 17.1 avg)

Pulling my cargo trailer (2k lbs maybe) MPG is better in tow haul mode.

I've noticed grade braking comes on less in tow haul mode.

As for trans temps, I did watch it for a bit with the car carrier and say 135-145. Stopped at a rest stop and when I started back up it was up to 149 (went up parked) but dropped back down with a mile of driving.

Our first big outing will be in a month, about 85 miles to the CG. I'm going up alone mid week and the family will join on the weekend so I'll have lots of time to observe things.

[LKicklight]

Check your owners manual, mine states, that when driving on flat to semi flat ground, it is not necessary..only when your transmission starts wanting to go in and out of passing gear...been driving around the south only using it when asked for...great gas mileage increase...157,000 on 20001 2500HD GAS..Silverado Ext. Cab..

[elind]

I pulled my 7000# TT with my 2008 GMC 5.3 V8 last summer when the outside temp was 90 degrees. The tranny would run 190 F on the flats and up to 210 F on the big hills. No alarms going off. I was told that the fluid will hold up to 275 F, but needs to be changed more often depending on how hot you run it. I plan to change mine every 20,000 miles or less/

[TexasBob]

Originally Posted by mduff

Originally Posted by mduff

It is understood that this changes the shift points for the transmission; shifts earlier, runs engine RPMs higher.

With a six speed transmission it is hardly noticeable.

[RenoRock]

A alternative to the ScanGuage II at $160 that can show you even more information logged and real time, in addition to the ability to view and reset fault codes:

Torque Pro for the android phone ($5) https://play.google.com/store/apps/d...l.torque&hl=en Torque — OBD2 Performance and Diagnostics for your Vehicle
Bluetooth OBDII adapter ($15) from ebay. Buy from US shipper with good ratings.
torque obdii bluetooth | eBay

Back to the original discussion, temps around 150-170 towing up some hills in Eastern TN. As a practice, I usually monitor transmission temps and fuel ranges, so I don't know if it would come up automatically. Next trip will be only about an hour on flat roads to the Richmond NASCAR race, but if I see something come up automatically I'll repost.

[SYE]

I have a guage on mine, it rerely goes above 200 degrees when I am towing my 12000 pound trailer. It sometimes will if I am going uphill. I have never seen it go above 220 Degrees. I also have a 4:10 rear end.

[sail2liv]

Temps 2500hd gas 6.0 3.73 trans 133-144 flat 160 mountains....w tow haul....
No tow haul on the flat.....only when up and down hills...then tow haul....truck loaded and towing 8500....GCW 15000 to 15500.....GCWR 16k

[TURBS]

When I had my 2005 2500hd gasser and 13k + trailer 190 -200 degrees towing no matter what with a hayden thermostatic controlled electric fan.

Turbs

[mjones12]

I think I discovered what happened. I went back out to the truck and scrolled through the screens, and it happens that the transmission temp screen comes up right after the trip meter screen. I think when I started out I pulled up the trip meter, pushed the button again to reset the mileage and didn't notice that I didn't hold the botton long enough for the reset. Instead, I moved to the next screen in the rotation, which was the transmission temperature. So, I'm speculating now that it didn't pop up on its own at all. I think it was operator error and lack of attention to detail.

Thanks to all who answered. I actually got some very good and useful information out of the discussion. Next time, I'll try not to panic before analyzing the perceived problem.

[PopBeavers]

Originally Posted by mduff

Our TT is approximately the same weight range, no issue with towing although only a couple of times late last season. Assuming that your towing package included the transmission cooler (just a thought); we installed one on our previous 4.8 Silverado and it made a significant difference on the transmission temperature.


It is understood that this changes the shift points for the transmission; shifts earlier, runs engine RPMs higher.

It also changes the voltage to the 12 volt charge line, but that is beyond the scope of this thread. There may be other things that tow/haul alters.